Free Online Tool
Ohms Law Calculator
Use the V=I×R relationship to calculate common circuit values directly in your browser.
The result will appear here.
How to Use
- Enter any two values among voltage, current, resistance, and power.
- Click calculate.
- Review the remaining values with units.
Examples
- Calculate 250Ω from 5V and 0.02A
- Calculate 2A and 24W from 12V and 6Ω
Calculation and Conversion Notes
The calculation is based on Ohm's law, `V = I × R`. Power uses `P = V × I`, `P = V^2 / R`, and `P = I^2 × R`. The tool calculates the remaining values from the combination of values you enter.
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